2. Materials and methodsThis study used six different bladed weapons (Fig. S1): a Japanese-style k*tana, an Arabian-style scimitar, a ‘‘krisblade’’ (wavy blade) broadsword, a Samburu short sword, a machete, and a hunting knife. All weapons were purchased commercially in the United States except the Samburu sword, which was bought from a traditional blacksmith in Maralal, Kenya.